The young couple, who returned my lost wallet, left ______ I could ask for their names.
The rise of oil prices made scientists search for new energy re-sources to __________ oil.
The parents couldn't tolerate __________ the messy __________ in the room.
The speed of cars is usually limited __________30 miles per hour on the busy city street.
__________ around the fire, the tourists danced with the local people.
We tried to __________ our point that drugs are more than physically harmful, but he just wouldn't listen.